Bad service

Was at Vodacom Midway Newlands was serviced by a guy who's name was NKOSI ZULU and he can't talk to clients properly he has an attitude and didn't resolve or answer the question that I had coming in the store .the reason I went in the store was to enquire because Vodacom is a ***** I finished my contract in 2020 and my statements came back -700 which shows they owe me but a few months later that was changed to 0.00 for over 2 years and recently after 3 years of not owning them nothing i am getting harassed that i owe R2500 and I have been handed over to legal they call me everyday and I have to explain the same thing to becoming annoying